Python GAE-urlfetch多部分post无法处理大文件

我试图将位于Blobstore中的文件从GAE发布到另一个HTTP服务（virustotal）

当前代码段适用于小文件（1-2MB）：

当我将此代码段用于大文件（18MB）时，会出现以下异常：

Traceback (most recent call last):
  File "C:\Program Files (x86)\Google\google_appengine\google\appengine\tools\devappserver2\api_server.py", line 162, in _handle_POST
    api_response = _execute_request(request).Encode()
  File "C:\Program Files (x86)\Google\google_appengine\google\appengine\tools\devappserver2\api_server.py", line 120, in _execute_request
    make_request()
  File "C:\Program Files (x86)\Google\google_appengine\google\appengine\tools\devappserver2\api_server.py", line 115, in make_request
    request_id)
  File "C:\Program Files (x86)\Google\google_appengine\google\appengine\api\apiproxy_stub.py", line 109, in MakeSyncCall
    'The request to API call %s.%s() was too large.' % (service, call))
RequestTooLargeError: The request to API call urlfetch.Fetch() was too large.

---

谢谢

应用程序引擎的urlfetch服务。如果你有一个付费应用程序，你可以使用sockets（我建议使用httplib来简化你的代码，但一定要这样做）

Traceback (most recent call last):
  File "C:\Program Files (x86)\Google\google_appengine\google\appengine\tools\devappserver2\api_server.py", line 162, in _handle_POST
    api_response = _execute_request(request).Encode()
  File "C:\Program Files (x86)\Google\google_appengine\google\appengine\tools\devappserver2\api_server.py", line 120, in _execute_request
    make_request()
  File "C:\Program Files (x86)\Google\google_appengine\google\appengine\tools\devappserver2\api_server.py", line 115, in make_request
    request_id)
  File "C:\Program Files (x86)\Google\google_appengine\google\appengine\api\apiproxy_stub.py", line 109, in MakeSyncCall
    'The request to API call %s.%s() was too large.' % (service, call))
RequestTooLargeError: The request to API call urlfetch.Fetch() was too large.